Alain Resnais's Last Year in Marienbad is now 50 years old, but it is more brilliant than ever – profoundly mysterious and disturbing, a para-surrealist masterpiece whose nightmarish scenario appears to have been absorbed from Buñuel and Antonioni and transmitted onward to Greenaway. In a colossal, eerie mansion, the well-dressed classes pass the time at some eternal house party. Are they in limbo, in hell, in heaven? One handsome man (Giorgio Albertazzi) expectantly approaches a beautiful woman (Delphine Seyrig), alluding to their clandestine romantic encounter the previous year – but she claims never to have met him before. Who is telling the truth? What really happened last year? What is really happening now? All these people, apparently so replete with culture and civilisation, are utterly, frozenly empty, and the truth seems to vanish in a glittering world of misleading surfaces and perspectives. Perhaps, 50 years on, it is time to consider a straightforward psychological realist explanation: last year, their flirtation escalated into something shocking and transgressive – this man raped the woman, and both have gone into amnesiac shock and denial. All we see on screen, the bizarre somnambulist behaviour, the anxiety and confusion, are delusional symptoms. For what it's worth, that is my reading of Marienbad. This superb film will continue to generate many more.